The present invention relates to novel benzoxazine-3-one and benzothiazine-3-one derivatives which carry in the 2-position a piperazinoalkyl group substituted by a heterocycle, and the corresponding 3-thione derivatives and salts thereof; to processes for preparing such compounds, and to pharmaceutical compositions containing such compounds.
1,4-Benzoxazine-3-one derivatives which carry a phenylpiperazinoalkyl group in the 2-position are known from published European patent application No. EP 233,728. These compounds have pronounced hypotensive and vasodilating effects.